The present invention generally relates to mechanical polishing devices. The present invention specifically relates to a polishing device useful for polishing a plurality of components such as a batch of multi-layer electronic components.
Barrel polishing is a common step performed during the manufacturing process of multi-layer electronic components, for components such as inductors, beads, capacitors, and oscillators. Polishing is necessary in order to round the corners and remove sharp edges from these components. Current polishing processes typically place a large number of components inside of a horizontal, rotating barrel, and expose the components to an abrasive that slowly polishes the edges of the components as the contents of the barrel are rotated.
There are many limitations of existing polishing devices when used for polishing multi-layer electronic components. Horizontal barrel devices must be operated at low speed in order to prevent damage to components, which results in a long polishing process. Other types of devices that are used to polish large mechanical workpieces, printed circuit boards, or semiconductor wafers generally cannot be used with small, multi-layer components. Many of these polishing devices often result in uneven polishing or damage to multi-layer electronic components.
Conventional horizontal-type barrel finishing systems are big and heavy, relatively inefficient, and do not provide polishing speed as fast as vertically oriented barrel finishing systems. For example, a horizontal barrel polishing process for multi-layer electronic components may take twelve hours for a single batch of components. This results in a longer floor to floor time for the overall manufacturing process. Horizontal barrel polishing techniques may also cause severe collisions due to the combination of gravity, revolution centrifugal force, and rotation centrifugal force.
Vertical barrel polishing techniques generally result in fewer collisions and therefore cause less damage than horizontal techniques. Some vertical barrel finishing devices exist in the art but have not been effectively adapted for use in electronic component polishing. For example, vertical planetary ball mills may be used to grind or mix solid particles of different granularities and materials, with use of both dry and wet methods. When vertical planetary ball mills are used for barrel polishing, however, all of the components will fail to properly circulate within the barrel which results in incomplete polishing batches.
What is needed is a low cost, high speed barrel polishing device useful for polishing multi-layer electronic components. The present invention provides such a device that can achieve uniform polishing, while reducing the incidence of cracking and damage during the barrel polishing process.